SU814860A1 - Method of producing modified dispersed silica - Google Patents

Description

one

The invention relates to the technology of producing modified dispersed silicas with phenols and can be used in the production of specific sorbents, as well as fillers for polymers, lubricants, varnishes, pigments, etc.

A known method of producing modified dispersed silica by treating it with phenol in an aqueous medium or in an environment of organic solvents.

There is also known a method for producing modified dispersed silica by vapor-phase treatment of the latter with phenol at 37 ° -385 ° C I.

The disadvantage of this method is the high process temperature.

The purpose of the invention is to reduce the temperature of the process.

The goal is achieved by the use of silica fume as silica, containing in the grafted layer associated with the silicon atom of the amino group, with silica fume and phenol

used at a molar ratio of 1: 0.1 to 1.2.

The method is carried out as follows.

In a sealed reactor is placed aminoaero and phenol in a molar ratio of 1: (O, 1-1,2). A vacuum is created on the order of 1.10 mm Hg. Art. and, the mixture is heated to 1OO-12 ° C for 1 hour. After that, at the same temperature, vapors of unreacted phenol and the reaction by-products are pumped out. The resulting modified phenol aerosil is cooled. to room temperature and discharged.

Example. In a sealed laboratory reactor, 1, O kg of amino aerosil containing 10 g of phenol on the surface of the sSi-NH2H group is placed. A vacuum of about 1.1 mm Hg is created. and heat the mixture to 1OO C for 1 hour. Then, at the same temperature, the vapors of unreacted phenol and side reactions are pumped out. The resulting phenol silica modified is cooled to room temperature and discharged.

The presence of grafted phenoxyl groups is determined spectrally by the absorption bands (, 162 O, C-C ZO60, 3090) characteristic of phenol in the IR spectrum of aerosil. The amount of phenoxyl groups on the surface of aarosil is determined by the gravimetric method by calcining the sample in air at 500-600 ° C. It is 0.1 mmol.

PRI mme R 2. V. a hermetic laboratory reactor is placed 1.0 kg of amio aerosyl containing on the surface of the group (O g of chlorophenol. Vacuum is created in the order of 1, 10 mm Hg and the mixture is heated to BUT C for hour. Then, at this temperature, the unreacted phenol vapors and the reaction products are pumped out. The resulting phenoxnaerosil is cooled to room temperature and discharged.

The amount of hlcherephenyl groups on the surface of aerosil is. 0.5 mmol / g.

P nmeper 3, A 1.0 kg amino acid aerosil is placed in a sealed laboratory reactor containing on the surface of the Е51-0-Зч group (95 g pe3qDHnHa. Create a vacuum on the order of 1.1 O mmHg, heat the mixture to 12 RSF and maintain this temperature for 1 hour. After that, at the same temperature, unreacted phenol vapors and reaction byproducts are pumped out. The resulting oxaneosyl is cooled to room temperature and discharged.

The quality of the resorption groups is 0.7 mmol / g.

As can be seen from the examples, the proposed method is compared with the known one; it has the advantage that the temperature of modifying the silica with phenols does not exceed. This may allow the synthesis to be carried out directly in a mixture with polymers, which are usually destroyed at a temperature above 120 ° C,

Claims (1)

Invention Formula 1, a method for producing a modified dispersed silica by vapor-phase treatment of the latter with phenol, characterized in that, in order to reduce the process temperature, As silica, aminosilicate is used, containing in the graft layer bound to the silicon atom of the amino group, 2, the method according to claim 1, about tl and h and y and with the fact that silica fume and phenol are used at a molar ratio of 1; 0.1 to 1.2, Sources of information taken into account in the examination 1, Utsuki et al. Surface treatment of silica gel with alcohol-containing solutions containing functional groups and phenol in acetone or hexane and the state of the adssrbated groups, Zaire, No. 238, 22 ,. 1973, p. 673-679 2, USSR author's certificate according to application no.2658284, cl, C 01 B 33/18, 14.08,78 (prototype).